European countries reported more than 10,000 excess deaths during the record-breaking heatwave that engulfed the west of ​the continent in late June, official data showed.

The vast majority — more than ‌9,000 — were among people aged 65 and above, according to ​data published by EuroMOMO, a network backed by the ⁠European Centre for Disease Prevention and Control and the World Health Organization.

Extreme heat can kill by causing heat stroke, or aggravating cardiovascular and respiratory diseases, with ‌older people among the most vulnerable.

“To have this kind of excess at this time of year is unusual. It’s ‌really high,” Lasse Vestergaard, Chief Physician at Denmark’s Statens Serum Institut, ‌which ⁠hosts EuroMOMO, told Reuters.

“It is difficult to explain this ⁠high excess mortality by anything but the extreme heat,” Vestergaard added.

Scientists have said the late-June heatwave would have been “virtually impossible” without human-caused climate change, which is making heatwaves ​more frequent and intense.

The ‌data, pooled from national mortality statistics in 27 European countries, included excess deaths from all causes, not just heat-related ones, during the week of June 22 to 28, when the heatwave peaked in ‌France, Spain, Britain and other countries.

But scientists said there were ​no other known major factors, such as COVID-19 outbreaks, that would have contributed to the spike to 10,650 excess ⁠deaths in that week.

The same European countries’ combined mortality over the previous eight weeks was, on average, around 500 deaths per week below typical ‌levels. The EuroMOMO data could be revised in future weeks as more data comes in.

The extreme heatwave at the end of June disrupted power supplies, shut schools, and smashed temperature records in France, Spain and the UK.

EuroMOMO does not publish excess deaths per individual country, but it noted that France and Belgium were the only ‌two countries in Europe to log “very high excess” mortality in the last week of ​June.

Belgium’s excess mortality was the highest during any heatwave in records going back to 2000, according to the country’s public ⁠health institute Sciensano.

A separate scientific study, published on Monday, estimated 2,700 people ⁠died from heat-related causes in England and Wales alone, during the May and June heatwaves.

Of those deaths, 42% were ‌caused by the extra heat that global warming contributed to the heatwaves, according to the findings by Imperial College London, the UK ​Met Office and the London School of Hygiene & Tropical Medicine.

The World Health Organization said on Sunday (June 28, 2026) that over 1,300 excess deaths had been recorded in Europe since June 21 in connection with the record-breaking heatwave roasting much of the continent.

Tens of millions have been braving a weekend of extreme temperatures in Europe as a deadly heatwave moves eastwards, with some countries announcing rising death tolls and health services warning of saturation.

On Sunday morning (June 28, 2026), French health officials said there had been around 1,000 more deaths than expected in that country just since Wednesday (June 24, 2026).

And across Europe, “more than 1,300 excess deaths have been recorded since 21 June linked to high temperatures in Europe”, WHO chief Tedros Adhanom Ghebreyesus said on X.

“Heat stress is often called the ‘silent killer’ – and European homes, workplaces and schools were not built for these temperatures,” he said.

At least 191 million people are forecast to endure temperatures of at least 35℃ on Sunday (June 28, 2026) in Europe, with the heat particularly intense in Germany, the Czech Republic, Hungary and Poland, according to AFP estimates.

A total of 381 million people in Europe, excluding Türkiye, will see temperatures surpass 30℃, according to analysis based on forecasts from the German Meteorological Service and 2025 population projections from the Joint Research Centre collated by Austrian NGO Klimadashboard.

Millions of people across the continent are currently “living under extreme heat, hundreds have died, schools are shut, grids are buckling”, Mr. Tedros warned.

“Driven by climate change and global warming, the phenomenon of the ‘once-in-a-generation’ heatwave is now occurring nearly annual,” he said, pointing out that “Europe is the fastest-warming continent on Earth, heating at twice the global average”.

The WHO chief said the United Nations health agency was “working with its Member States and partners to address the health threats posed by extreme heat through focusing on preparedness, prevention and stronger health system responses”.

He called on European countries to “implement heat health action plans”, as part of a push to safeguard health in the face of climate change.

More than 62,700 people died in Europe from heat-related causes in 2024, according to research published in Nature Medicine on Monday (September 22, 2025), with women and the elderly representing the largest part of the death toll.

Researchers at the Barcelona Institute for Global Health, known as ISGlobal, who obtained daily mortality records from 32 European countries, estimated over 181,000 people died from heat-related complications over the summer months of 2022 to 2024.

Heat index: how heat-stressed are you?

Between June 1 and September 30, 2024, the mortality rate rose by 23% from the same period a year earlier, although the number of deaths was still just below the 67,900 deaths recorded in 2022, the first year of the study.

“This number is saying to us that we should start adapting our populations,” said Tomás Janos, the lead author of the study.

Hottest summer on record in Europe

The summer of 2024 was the hottest on record in Europe, according to the European Union’s Copernicus Climate Change Service.

Two-thirds of the estimated deaths occurred in Southern Europe. Italy, which has Europe’s largest population of elderly proportionally, and experienced soaring temperatures all three summers, had the highest absolute death toll each summer.

Though summer 2025 was not part of the study, the Italian Society for Emergency Medicine said emergency room admissions rose by up to 20% in certain regions during peak temperatures this year, indicating that the country is still grappling with heat risk for the elderly.

“Patients who were already frail and suffering multiple ailments required more hospital care, which increased pressure on hospital services, as happens during periods of influenza surges,” said Alessandro Riccardi, president of SIMEU, told Reuters.

European health authorities increasingly provide heat warnings when temperatures are expected to meet official definitions of a heatwave that vary from country to country.

Janos, however, said heat-related mortality is noticeable even at temperatures as low as 24 degrees Celsius (75.2°F) for certain populations in specific locations.

Protection from heat should be ‘an essential medicine’

Gerardo Sanchez, an official at the European Environment Agency, who is part of the expert group revising the World Health Organization’s heat health guidelines, said data on heat-related deaths needed to be matched by long-term investment to improve Europe’s built infrastructure and access to cooling.

“Protection from heat needs to be treated as an essential medicine for those that need it the most,” Sanchez told Reuters.

ISGlobal said it had undercounted heat deaths for 2022 and 2023, which had been calculated on weekly, not daily, records, and revised their previous estimates slightly upwards.